From 'aman (in the sense of training); an expert -- cunning workman.
see HEBREW 'aman
H542. omman
אָמָּן (omm¹n) noun masculine master-workman, artist Cant 7:2 (Mishna, Talmud אוּמָנוּת אוּמָן, handiwork, Syriac ᵑ6 Exodus 28:11, where = Hebrew חָרָשׁ & is likewise used of gems; Nabataean אמנא Vog94, Assyrian mar umm'ni, LyonSargontexte 65, compare ZimBP 12; compare II. אָמוֺן).